MockRedis provides the same interface as
redis-rb, but it stores its
data in memory instead of talking to a Redis server. It is intended
for use in tests.
The current implementation is tested against Redis 4. Older versions of Redis may return different results or not support some commands.
It's as easy as
require 'mock_redis'; mr = MockRedis.new. Then you can
call the same methods on it as you can call on a real
>> require 'mock_redis' >> mr = MockRedis.new >> mr.set('some key', 'some value') => "OK" >> mr.get('some key') => "some value"
mock_redis supports most of the methods that redis-rb does. Examples of supported methods:
- String methods:
- List methods:
- Set methods:
- Hash methods:
- Sorted set methods:
A MockRedis object can't do everything that a real Redis client can since it's an in-memory object confined to a single process. MockRedis makes every attempt to be Redis-compatible, but there are some necessary exceptions.
Blocking list commands (
#brpoplpush) work as expected if there is data for them to retrieve. If you use one of these commands with a nonzero timeout and there is no data for it to retrieve, then the command returns immediately. However, if you ask one of these commands for data with a 0 timeout (means "wait forever") and there is no data available, then a
MockRedis::WouldBlockexception is raised. It's not what a real Redis client would do, but it beats hanging your test run forever.
#infojust returns canned values; they don't update over time.
#sortsupports ascending and descending sort.
ALPHAsort is not yet supported.
Some stuff, we just can't do with a single Ruby object in a single Ruby process.
Debugging commands (
#debug('segfault')) aren't available.
#objectisn't available since we don't have any Redis internals to poke at.
#monitorisn't available; there's no place for requests to come from, so there's nothing to receive.
Pubsub commands (
#punsubscribe) aren't available.
Scripting commands (
#evalsha) are just stubs—they won't execute anything
There are some things we want to have in here, but that we just haven't gotten to doing yet. If you're interested in helping out, please submit a pull request with your (tested!) implementation.
#config(:get|:set|:resetstat)isn't done. They can just return canned values.
As of version
0.19.0, Ruby 2.2 and above are supported. For
older versions of Ruby, use
0.18.0 or older.
Running the Tests
If you want to work on this, you'll probably want to run the
tests. (Just kidding! There's no probably about it.) These tests were
written with Redis running on
localhost without any passwords
required. If you're using a different version of Redis, you may see
failures due to error message text being different. If you're running
a really old version of Redis, you'll definitely see failures due to
stuff that doesn't work!